Define a period

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How many working days in year 1991?

Here is the detail of the calculation:

Because 1991 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 6 public holidays that do not fall during a weekend and we obtain 255 working days in 1991.

Here is the list of these 6 public holidays:

1. New Year's Day : Tuesday, 1 January, 1991
2. National Sovereignty and Children's Day : Tuesday, 23 April, 1991
3. Labour and Solidarity Day : Wednesday, 1 May, 1991
4. Victory Day : Friday, 30 August, 1991
5. Republic Day Eve : Monday, 28 October, 1991
6. Republic Day : Tuesday, 29 October, 1991

And here is the public holiday falling on a weekend:

1. Commemoration of Atatürk, Youth and Sports Day : Sunday, 19 May, 1991